Three-dimensional display devices such as three-dimensional television receivers and head-mounted displays that are configured to present videos in a stereoscopic manner are in use. Devices capable of stereoscopically presenting videos on portable terminals such as mobile phones and potable game machines have also been developed, thereby increasing the chances for general users to view stereoscopic videos.
A three-dimensional display device for displaying a stereoscopic video realizes stereoscopy of an image by a user by having the user view images having a parallax to the left and right eyes. There are available a method of using special optical glasses for presenting images having a parallax to the left and right eyes and a method of using a parallax barrier or a lenticular lens instead of optical glasses.